1. Field of the Invention
This invention relates to a printing method, and in particular, it relates to a toner-saving printing method that removes dark colored background before printing.
2. Description of the Related Art
Many documents, especially documents that are intended to be viewed using a display screen or projector, such as web pages and PowerPoint® documents, have a dark solid color or patterned background for visual appeal. When such documents are printed, it is often desirable to print the background with a lighter color or no color (white) to save toner or ink. Some application software, such as PowerPoint®, provides printing modes that allow a page having a dark background to be printed with a light background or no background in certain instances. Internet Explorer also has the ability to display a web page with a dark background and print the page with a white background. In another example, U.S. Pat. No. 6,297,796 to Letts et al. describes a method and apparatus, used in an oscilloscope or other test and measurement instrument, “for inverting a color display on a dark background to produce a display on a substantially white background suitable for printing, [which] maintain[s] the same apparent relative intensities in both the LCD display on a dark background and the hardcopy displayed on a light background. The apparatus includes a memory including a first palette for the LCD display, a second palette for the hardcopy display, and a look-up table. A controller accesses the first and second palettes and look-up table for converting display data from LCD data to color-inverted printer data.” (Abstract.)